In situations where a format used by newly installed storage software differs from a format used by previously installed storage software, migration operation may be performed on data managed by the previously installed storage software while also converting the data to the format of the newly installed storage software. When a free space available in a first location in the storage system is less than a size of the data in the format used by previously installed storage software, a problem exists that the data cannot be copied to the format used by the newly installed storage software and stored at the first location. Furthermore, users may want access to their objects without having to wait for their objects to be migrated to the format used by the newly installed storage software. Accordingly, it may be desirable to manage the migration operation to make the data which is to be migrated available during the migration operation.